SFC cartridge development

I find that :



It's a official cartridge.
Is-it a interesting thing ?
I don't collec SFC (only PCE), then I am not very interesting by it.

 

Probably a Flash cartridge? Can you possibly open it (with the right screwdriver of course :lol

 

It's probably not a flash cartridge, I'd guesss that it's just to extend pins to the ribbon. ("EPROM emulator" on the other end of the ribbon)

 

Kammedo : I don't have the right screwdriver, but I think a friend have one. But I can only see him the next week.

 

this is just a guess, but im assuming it doesnt actually contain any hardware apart from an extension of the adress/data bus to the blue connector and a cic.
as calpis already said, its most likely part of some rom emulator. you will not be able to put this cartridge to good use unless you find the actual rom emulator, the computer interface card and the software that went with it.

 

It would surely be intresting to have a look at its inside...

 

I will try to do this the next week.

 

A picture of the inside :

 

COuld be official, the name of the PCB is Peach 7 so ...

 

It's a simple parallel interface (8255), the ROM is some sort of IPL (likely is used with other equipment), the 74138 is to decode the 8255.

 

Could it be a part of a demo setup? For example, I have a Genesis store demo system comprised of:

-a cart with a ribbon-cable interface like the one pictured above
-the cart is basically a bootloader that tells the Genny to read data from the demo box instead of the cart itself
-ribbon cable connects to a big metal box that 6 Genesis carts are loaded in to
-the box has a switch to choose games and a timer to limit demo play

Having the board marked "Peach 7" might indicate the demo setup housed seven carts.

 

Can you post picture of this extrarice please ?

 

No, it's definitely not part of a demo setup, address/data bits would have to be go over the IDC ribbon which they do not. Almost certainly it's part of another kit, which uses this as a means to communicate with other hardware (probably a PC.)

 

That's an EPROM (obviously), have a look here for a similar component from TI :
http://pdf1.alldatasheet.com/datasheet-pdf/view/29037/TI/TMS27C512-15JL.html

EDIT : if someone finds the exact DS for it please post the link here!

EDIT :
and here's the 8255 pinout :
http://pdf1.alldatasheet.com/datasheet-pdf/view/119081/NEC/UPD8255AC-2.html


It shouldnt be too hard to be able to read the rom's data...Thibaut, what do you think about giving it a try?

 

With a 64K EPROM on it...a simple code ROM or likely?

Almost certainly it will use 2 (of the 3 8255) ports for adressing (EPROM is 64K) and 1 for data...which would require a 3 byte write / 2 byte write and one read operations from the PC. It really shouldn't be too hard to dump the EPROM - if there's anything at all on it of course!

 

Yes, it's a "code" ROM but you're confused; the SNES controls the 8255, not a PC.

There is no reason why you need an exact datasheet for a specific ROM; 27 series ROMs are JEDEC compliant. A 27C512 is a CMOS 27512, that is a 512K(bit) ROM (64KiB) arranged as 64K(bit) x 8 bits.

 

Yeah I'll get some pictures up tomorrow.

 

Hah didnt truly think about this possibility .
But does it have any sense? I mean, 8255 is 3 ports, one would do the job as well since the SNES databus is only 8 bit. Which use would the other two have?
The only reasonable configuration i can think of is one port to the EPROM and two to the PC, one for writing and one for reading..

 

The 8255 does not access the ROM at all, that wouldn't make any sense. The ports are also bidirectional so each port can be used for reading AND writing just like the SNES's data bus. I have no idea what the 8255's I/O ports are for but they (all of them that are used are) are routed to the IDC pins.

The SNES decodes the ROM, the cartridge decodes the 8255. The SNES cannot see the 8255, only the code in the ROM assumes it's there and blindly writes to it's registers.

 

How about fetching code?

So its some kind of SNES - PC interface.